The secretary general of the International Seabed Authority says little is known about the consequences of deep sea mining.

A four-day workshop in Fiji this week, organised by the authority and the applied geoscience and technology division of the Secretariat of the Pacific Community, aims to draw up recommendations for environmental impact assessments of seabed mining.

The authority governs the parts of the seabed outside of national jurisdictions.

Nii Allotey Odunton says with a rise in demand for copper, nickel, manganese and cobalt and an accompanying rise in the regulations around their land-based extraction, seabed mining is becoming increasingly attractive.

"There was one test in the 70s that actually recovered nodules from the seabed. We've had over 40 years of little experiments. There's been no minnig in the deep seabed yet. So we don't have any actual data that comes from mining. What we are trying to do is to be as responsible as possible."

Nii Allotey Odunton says prospective miners must take out an exploratory licence which requires them to submit baseline data to the authority.